Asialofetuin

D. K. Mandal and C. F. Brewer, Crosslinking activity of the 14-kilodalton -galactose-specific vertebrate lectin with asialofetuin Comparison with several galactose-specific plant lectins, Biochemistry, 31 (1992) 8465-8472. 

However, the azide-based protocol often has problems with the formation of byproducts under both azide formation and subsequent reduction. 388 Therefore, mainly aminolysis is used. Glycosylamines are prepared from GlcNAc, GlcNAc2, Glc, maltotriose, mal-toheptaose, and di- and triantenneary complex glycans, isolated from asialofetuin by preparative hydrazinolysis. A modification of the method by Likhosherstov is also employed. 379 ... 

Scheme 40 Large Oligosaccharides Isolated from Asialofetuin (Complex-Type) and Ribonuclease B (High-Mannose-Type) by Hydrazinolysis[1491...

Derivatization of the Mixture of the Tri- and the Diantennary Asialofetuin Oligosaccharides with Fmoc-Asp(ODhbt)-OtBu (150) 149 ... 

Substrate-specificity studies on microsomal, frog-liver sialyltrans-ferase revealed the presence of (2—>3) and (2—>6) activities.277 This enzyme system readily sialylates oligosaccharides, but is almost inactive with asialofetuin, which is in contrast to the sialylation of oligosaccharides, as well as asialofetuin, by rat-liver sialyltransferase.278 The conclusion from this observation is that acceptor specificity of sialyl-transferases isolated from liver of evolutionary distant animals is similar for substrates of low molecular weight, but differs for compounds of high molecular weight.279... 

Commercially obtained preparations of ricin A chain and abrin A chain may require further purification to eliminate traces of contaminating toxin B chains. The simplest procedure is to pass the A chain preparation over a column of Sepharose-linked asialofetuin, to which the B chains bind avidly (4,11)... 

After immobilization the grafted surfaces were probed by lection recognition and cell activity tests. Data were correlated with analytical data from XPS and ToF-SIMS. Alio A lectin binding was performed on y -sterilized ELISA plates. The wells were modified with different concentration of MAD-Gal. Inhibition tests were performed on surfaces modified with 0.25 mM solution of MASD-Gal and asialofetuin (1 mg/ml) as an inhibitor. Figure 4 summarizes the results. 

Asialofetuin is an asialoglycoprotein containing terminal galactosyl residues that have been used to target liposomes to the liver. There was seven-fold enhancement in CAT expression in the liver when succinylatcd asialofetuin was added to preformed plasmid/ DOTAP Chol complexes to provide a ligand for hepatic asialoglycoprotein receptor. 

Kalhnteri, P., Papadimitriou, E., and Antimisiaris, S. G., (2001), Uptake of hposomes which incorporate a glycopeptide fraction of asialofetuin by HepG2 cells, / Lipos. Res., 11,175-193. 

Nuclease Resistance of Asialofetuin-Lipoplexes by Agarose Gel Electrophoresis... 

Wu J, Liu P, Zhu JL, Maddukuri S, Zern MA (1998) Increased Hver uptake of liposomes and improved targeting efficacy by labelling with asialofetuin in rodents. Hepatology 27 772-778... 

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